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Anesthesiology/Preoperative preparation


Hi Dr. Rex,

Just a few general questions regarding my studies in General Surgery (I couldnt find a general surgeon here so i hope you dont mind).

1. Why is a preop urinalysis indicated in all implant cases?

2. What range of PT/INR is acceptable for a case to be posted?

3. Is there any latest and universally accepted method for preopereative cardiac risk stratification?

4. How do you go about giving titrated beta blockers (and what class and dosing schedule) for high cardiac risk patients perioperatively?

5. What anaesthetic drugs can predispose to postop renal failure?

Thank you so much for your time.


1. done to rule out UTI, since implants generally must be removed in if they get infected and this risk increases in a patient w/ UTI.
2. that is surgeon,pt, case dependent. no uniform rule. Generally however, like to see INR <1.5
3. Revised Cardiac risk index is being used-this is a fairly complex topic: considers pts medical hx related to coronary artery disease, congestive heart failure, creatinine level, hx of diabetes requiring insulin, hx of stroke or TIA, and type of surgery (major, intermediate or low risk).
4. generally b-blockers are only indicated in patients already on them.  For everyone else, clinician dependent.  There is evidence to suggest that pts with 2 to 3 risk factore (see above) undergoing vascular surgery, may benefit; however, in general, studies suggest that patients should be started AT LEAST 1 week prior to surgery and have beta blocker titrated carefully to HR < 65 bpm.  There is more to this however.
5. None that I'm aware of.  This is more related to patient related factors (i.e. pre op renal insufficiency and fluid mismanagement intraop and post op-i.e. hespand 6% [linked], hypovolemia0.

Dr. Russell


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Rex Russell


Any question dealing with general anesthesia issues. With particular emphasis on regional anesthesia.


I am a board certified anesthesiologist, graduated from residency in 2004 from Johns Hopkins Hospital. I have since worked as an anesthesiologist first in the Air Force for three years and then most recently in Texas in Private Practice.

Texas Medical Association Texas society of Anesthesiologists American Society of Anesthesiologists

BS, BYU MD, U of Texas, Galveston Intern-St. Joe's Hospital, Phx, AZ Internal Medicine Residency-Johns Hopkins Hospital, Baltimore, MD

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